Contributions
Abstract: PB2274
Type: Publication Only
Background
Hydroxyurea (HU) is the first-line agent recommended as a cytoreductive agent in the treatment of Phi-negative MPNs. The indication is based on the effectiveness in reducing the risk of vascular events in the short term and the risk of transformation to AML and MF in the long term. Its use continues to be controversial in published works regarding the prevention of thrombosis, prolongation of survival and transformation to MF and AML. Being a drug of simple handling in clinical practice, 11-20% of cases of intolerance have been reported and between 13-20% of resistance according to established criteria.Aims
Describe population of patients with HU, criteria of treatment initiation, vascular complications, remission rate, rates of intolerance, resistance to HU and progression in MPN treated in Argentina in the daily practice.
Methods
Members of the Argentine Society of Hematology (SAH) reported the data obtained from clinical histories of patients with NMP treated with HU. We analyzed, reason for treatment initiation, response, frequency of thrombosis, intolerance rate, resistance and mortality with descriptive statistics. Complete remission was considered for those patients with PV with Hto <45% and with TE with platelets <400000 / mm3 sustained for 12 weeks
Results
We included 419 patients referred by members of the SAH, diagnosed from 1986 to 2017, of which 417 were analysable, with a median follow-up of 67 (1-372) months; 63% female, mean age 63 years (SD 13.67), 206 patients with PV (49%), 180 TE (43%) and 31 FM (7.4%) Bone marrow biopsy was performed at 81%. Mutations were studied in 80.2%: JAK2V617F POS in PV (90.7%), TE (80%), MF (64%). Of 22 pac JAK2V617F NEG: 9 were CALR type 1 and 6 type 2, 4 MPL POS and 9 triple NEG. Splenomegaly was found in 43.2%. They received aspirin 81.3%. The reason for starting treatment was age (51%), followed by the presence of vascular risk factors (26.6%), thrombocytosis (24.7%) and previous thrombosis (16.8%). 62 patients had venous thrombosis, 48 prior to HU, 8 patients with 2 or more events, 16 had thrombosis with HU.58 had arterial thrombosis (CVA, TIA, AMI) 48 were previous to HU, 11 during the treatment.22 patients (20.2%) with major bleeding during HU treatment. Among the patients with PV, 61% maintained Hto less than 45%, and 66% of patients with ET achieved platelets less than 400,000 / mm3. A total of 136 patients (32.6%) with adverse events were reported, the most frequent were cutaneous, cytopenias and gastrointestinal symptoms. The incidence of neoplasms was 1.9%,t refractoriness 5% and 3.8% were intolerant. Progression to AML in 1.6% and to MF 2.6%. The progression-free survival was 282 months. The mortality was 4.8%. The overall survival was 295 months.
Conclusion
We can conclude that HU was effective in obtaining complete remissions in PV and ET, in reducing the risk of thrombosis. There were frequent side effects, mainly cutaneous ulcers, and a low rate of resistance / intolerance, progression and development of secondary neoplasia. The results obtained show that the evolution and complications of patients with PV JAK2 and JAK2 positive TE are similar and that the low rate of progression is probably related to the follow-up time, since this is directly proportional to the course of each decade of the disease and treatment. The active participation of the members of the SAH in the collection of data provides the basis for the creation of a prospective registry of MNP and the accomplishment of collaborative works within the framework of the SAH in the country and eventually in the region.Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): Hydroxyurea, Myeloproliferative disorder
Abstract: PB2274
Type: Publication Only
Background
Hydroxyurea (HU) is the first-line agent recommended as a cytoreductive agent in the treatment of Phi-negative MPNs. The indication is based on the effectiveness in reducing the risk of vascular events in the short term and the risk of transformation to AML and MF in the long term. Its use continues to be controversial in published works regarding the prevention of thrombosis, prolongation of survival and transformation to MF and AML. Being a drug of simple handling in clinical practice, 11-20% of cases of intolerance have been reported and between 13-20% of resistance according to established criteria.Aims
Describe population of patients with HU, criteria of treatment initiation, vascular complications, remission rate, rates of intolerance, resistance to HU and progression in MPN treated in Argentina in the daily practice.
Methods
Members of the Argentine Society of Hematology (SAH) reported the data obtained from clinical histories of patients with NMP treated with HU. We analyzed, reason for treatment initiation, response, frequency of thrombosis, intolerance rate, resistance and mortality with descriptive statistics. Complete remission was considered for those patients with PV with Hto <45% and with TE with platelets <400000 / mm3 sustained for 12 weeks
Results
We included 419 patients referred by members of the SAH, diagnosed from 1986 to 2017, of which 417 were analysable, with a median follow-up of 67 (1-372) months; 63% female, mean age 63 years (SD 13.67), 206 patients with PV (49%), 180 TE (43%) and 31 FM (7.4%) Bone marrow biopsy was performed at 81%. Mutations were studied in 80.2%: JAK2V617F POS in PV (90.7%), TE (80%), MF (64%). Of 22 pac JAK2V617F NEG: 9 were CALR type 1 and 6 type 2, 4 MPL POS and 9 triple NEG. Splenomegaly was found in 43.2%. They received aspirin 81.3%. The reason for starting treatment was age (51%), followed by the presence of vascular risk factors (26.6%), thrombocytosis (24.7%) and previous thrombosis (16.8%). 62 patients had venous thrombosis, 48 prior to HU, 8 patients with 2 or more events, 16 had thrombosis with HU.58 had arterial thrombosis (CVA, TIA, AMI) 48 were previous to HU, 11 during the treatment.22 patients (20.2%) with major bleeding during HU treatment. Among the patients with PV, 61% maintained Hto less than 45%, and 66% of patients with ET achieved platelets less than 400,000 / mm3. A total of 136 patients (32.6%) with adverse events were reported, the most frequent were cutaneous, cytopenias and gastrointestinal symptoms. The incidence of neoplasms was 1.9%,t refractoriness 5% and 3.8% were intolerant. Progression to AML in 1.6% and to MF 2.6%. The progression-free survival was 282 months. The mortality was 4.8%. The overall survival was 295 months.
Conclusion
We can conclude that HU was effective in obtaining complete remissions in PV and ET, in reducing the risk of thrombosis. There were frequent side effects, mainly cutaneous ulcers, and a low rate of resistance / intolerance, progression and development of secondary neoplasia. The results obtained show that the evolution and complications of patients with PV JAK2 and JAK2 positive TE are similar and that the low rate of progression is probably related to the follow-up time, since this is directly proportional to the course of each decade of the disease and treatment. The active participation of the members of the SAH in the collection of data provides the basis for the creation of a prospective registry of MNP and the accomplishment of collaborative works within the framework of the SAH in the country and eventually in the region.Session topic: 16. Myeloproliferative neoplasms - Clinical
Keyword(s): Hydroxyurea, Myeloproliferative disorder